Amazon Land Management Study: Algodón River

An aerial photo of the Algodón River flowing through a forest of the Amazon Basin in the remote northeastern corner of Peru. To explore the extent and scale of Indigenous modification of the Amazon, scientists collected and analyzed a series of 10 roughly 3-foot-long soil cores from three sites in this region, each located at least a half-mile (about 1 kilometer) away from river courses and floodplains.

Smithsonian scientists and their collaborators have found new evidence that prehistoric Indigenous peoples did not significantly alter large swaths of forest ecosystems in the western Amazon, effectively preserving large areas of rainforests to be unmodified or used in sustainable ways that did not reshape their composition. The new findings are the latest in a long scientific debate about how people in the Amazon have historically shaped the rich biodiversity of the region and global climate systems, presenting new implications for how the Amazon’s biodiversity and ecosystems can be best conserved and preserved today.

The new study led by Smithsonian researchers, published June 7 in the journal Proceedings of the National Academy of Sciences, suggests that for at least the past 5,000 years, large areas of the rainforest in western Amazonia located away from the fertile soils near rivers were not periodically cleared with fire or subject to intensive land use by the Indigenous population before the arrival of Europeans.